Extracting prog: 5m2.123431293s Minimizing prog: 30m31.145442873s Simplifying prog options: 0s Extracting C: 3m8.415770922s Simplifying C: 27m11.832488944s extracting reproducer from 1 programs testing a last program of every proc single: executing 1 programs separately with timeout 6m0s testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate detailed listing: executing program 0: r0 = openat$nullb(0xffffffffffffff9c, &(0x7f0000001000), 0x48882, 0x0) sendfile(r0, r0, 0x0, 0x400000000003f) r1 = dup(r0) fallocate(r1, 0x11, 0x8000000, 0x8004000000200) program crashed: INFO: task hung in blkdev_write_iter single: successfully extracted reproducer found reproducer with 4 syscalls minimizing guilty program testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup detailed listing: executing program 0: r0 = openat$nullb(0xffffffffffffff9c, &(0x7f0000001000), 0x48882, 0x0) sendfile(r0, r0, 0x0, 0x400000000003f) dup(r0) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-fallocate detailed listing: executing program 0: r0 = openat$nullb(0xffffffffffffff9c, &(0x7f0000001000), 0x48882, 0x0) sendfile(r0, r0, 0x0, 0x400000000003f) fallocate(0xffffffffffffffff, 0x11, 0x8000000, 0x8004000000200) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate detailed listing: executing program 0: r0 = openat$nullb(0xffffffffffffff9c, &(0x7f0000001000), 0x48882, 0x0) r1 = dup(r0) fallocate(r1, 0x11, 0x8000000, 0x8004000000200) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): sendfile-dup-fallocate detailed listing: executing program 0: sendfile(0xffffffffffffffff, 0xffffffffffffffff, 0x0, 0x400000000003f) r0 = dup(0xffffffffffffffff) fallocate(r0, 0x11, 0x8000000, 0x8004000000200) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate detailed listing: executing program 0: r0 = openat$nullb(0xffffffffffffff9c, 0x0, 0x48882, 0x0) sendfile(r0, r0, 0x0, 0x400000000003f) r1 = dup(r0) fallocate(r1, 0x11, 0x8000000, 0x8004000000200) program did not crash extracting C reproducer testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate program crashed: INFO: task hung in blkdev_write_iter simplifying C reproducer testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate program crashed: no output from test machine a never seen crash title: no output from test machine, ignore testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate program crashed: INFO: task hung in blkdev_write_iter testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate program crashed: INFO: task hung in blkdev_write_iter testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate program crashed: INFO: task hung in blkdev_write_iter testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate program crashed: INFO: task hung in blkdev_write_iter testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate program crashed: INFO: task hung in blkdev_write_iter testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate program crashed: INFO: task hung in blkdev_write_iter testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate program crashed: INFO: task hung in blkdev_write_iter testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate detailed listing: executing program 0: r0 = openat$nullb(0xffffffffffffff9c, &(0x7f0000001000), 0x48882, 0x0) sendfile(r0, r0, 0x0, 0x400000000003f) r1 = dup(r0) fallocate(r1, 0x11, 0x8000000, 0x8004000000200) program crashed: INFO: task hung in blkdev_write_iter validation run: crashed=true testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate detailed listing: executing program 0: r0 = openat$nullb(0xffffffffffffff9c, &(0x7f0000001000), 0x48882, 0x0) sendfile(r0, r0, 0x0, 0x400000000003f) r1 = dup(r0) fallocate(r1, 0x11, 0x8000000, 0x8004000000200) program crashed: INFO: task hung in blkdev_write_iter validation run: crashed=true testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-sendfile-dup-fallocate detailed listing: executing program 0: r0 = openat$nullb(0xffffffffffffff9c, &(0x7f0000001000), 0x48882, 0x0) sendfile(r0, r0, 0x0, 0x400000000003f) r1 = dup(r0) fallocate(r1, 0x11, 0x8000000, 0x8004000000200) program crashed: INFO: task hung in blkdev_write_iter validation run: crashed=true reproducing took 1h15m26.750141408s repro crashed as (corrupted=false): INFO: task syz.0.17:6033 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:23944 pid:6033 tgid:6032 ppid:5951 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 rwsem_down_read_slowpath+0x61e/0x920 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1539 inode_lock_shared include/linux/fs.h:1043 [inline] blkdev_write_iter+0x50b/0x710 block/fops.c:801 iter_file_splice_write+0x99b/0x1100 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x101/0x160 fs/splice.c:1161 splice_direct_to_actor+0x53a/0xc70 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x195/0x290 fs/splice.c:1230 do_sendfile+0x535/0x7d0 fs/read_write.c:1372 __do_sys_sendfile64 fs/read_write.c:1433 [inline] __se_sys_sendfile64+0x144/0x1a0 fs/read_write.c:1419 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0b3a59c629 RSP: 002b:00007f0b3b4e0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f0b3a815fa0 RCX: 00007f0b3a59c629 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000003 RBP: 00007f0b3a632b39 R08: 0000000000000000 R09: 0000000000000000 R10: 000400000000003f R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0b3a816038 R14: 00007f0b3a815fa0 R15: 00007ffe34502d38 Showing all locks held in the system: 1 lock held by ksoftirqd/1/23: #0: ffff8880b873ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 1 lock held by khungtaskd/31: #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5585: #0: ffff8880370010a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000331e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz.0.17/6033: #0: ffff88802384aa28 (&sb->s_type->i_mutex_key#11){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline] #0: ffff88802384aa28 (&sb->s_type->i_mutex_key#11){++++}-{4:4}, at: blkdev_write_iter+0x50b/0x710 block/fops.c:801 3 locks held by syz.0.17/6036: 4 locks held by syz-executor/13728: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 1331 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:switch_mm_irqs_off+0x354/0x690 arch/x86/include/asm/bitops.h:-1 Code: 93 4c 39 e0 0f 85 9d 00 00 00 e9 8f 01 00 00 83 fd 08 0f 83 0d 02 00 00 4c 89 f7 be 08 00 00 00 e8 21 3d b7 00 f0 4d 0f ab 27 <48> 8b 6c 24 10 4c 8d b3 b8 08 00 00 4c 89 f7 be 08 00 00 00 e8 d3 RSP: 0018:ffffc90005d6f710 EFLAGS: 00000056 RAX: 0000000000000001 RBX: ffff88813fe38c40 RCX: ffffffff8178590f RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88813fe397c0 RBP: 0000000000000001 R08: ffff88813fe397c7 R09: 1ffff11027fc72f8 R10: dffffc0000000000 R11: ffffed1027fc72f9 R12: 0000000000000001 R13: dffffc0000000000 R14: ffff88813fe397c0 R15: ffff88813fe397c0 FS: 0000000000000000(0000) GS:ffff888125566000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe3561456b8 CR3: 000000000e54c000 CR4: 00000000003526f0 Call Trace: use_temporary_mm+0x98/0x140 arch/x86/mm/tlb.c:1029 __text_poke+0x632/0x9a0 arch/x86/kernel/alternative.c:2581 text_poke arch/x86/kernel/alternative.c:2645 [inline] smp_text_poke_batch_finish+0xd36/0x1160 arch/x86/kernel/alternative.c:3034 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:899 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 final repro crashed as (corrupted=false): INFO: task syz.0.17:6033 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:23944 pid:6033 tgid:6032 ppid:5951 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 rwsem_down_read_slowpath+0x61e/0x920 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1261 [inline] __down_read kernel/locking/rwsem.c:1274 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1539 inode_lock_shared include/linux/fs.h:1043 [inline] blkdev_write_iter+0x50b/0x710 block/fops.c:801 iter_file_splice_write+0x99b/0x1100 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x101/0x160 fs/splice.c:1161 splice_direct_to_actor+0x53a/0xc70 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x195/0x290 fs/splice.c:1230 do_sendfile+0x535/0x7d0 fs/read_write.c:1372 __do_sys_sendfile64 fs/read_write.c:1433 [inline] __se_sys_sendfile64+0x144/0x1a0 fs/read_write.c:1419 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0b3a59c629 RSP: 002b:00007f0b3b4e0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f0b3a815fa0 RCX: 00007f0b3a59c629 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000003 RBP: 00007f0b3a632b39 R08: 0000000000000000 R09: 0000000000000000 R10: 000400000000003f R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0b3a816038 R14: 00007f0b3a815fa0 R15: 00007ffe34502d38 Showing all locks held in the system: 1 lock held by ksoftirqd/1/23: #0: ffff8880b873ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 1 lock held by khungtaskd/31: #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5585: #0: ffff8880370010a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000331e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz.0.17/6033: #0: ffff88802384aa28 (&sb->s_type->i_mutex_key#11){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline] #0: ffff88802384aa28 (&sb->s_type->i_mutex_key#11){++++}-{4:4}, at: blkdev_write_iter+0x50b/0x710 block/fops.c:801 3 locks held by syz.0.17/6036: 4 locks held by syz-executor/13728: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 1331 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:switch_mm_irqs_off+0x354/0x690 arch/x86/include/asm/bitops.h:-1 Code: 93 4c 39 e0 0f 85 9d 00 00 00 e9 8f 01 00 00 83 fd 08 0f 83 0d 02 00 00 4c 89 f7 be 08 00 00 00 e8 21 3d b7 00 f0 4d 0f ab 27 <48> 8b 6c 24 10 4c 8d b3 b8 08 00 00 4c 89 f7 be 08 00 00 00 e8 d3 RSP: 0018:ffffc90005d6f710 EFLAGS: 00000056 RAX: 0000000000000001 RBX: ffff88813fe38c40 RCX: ffffffff8178590f RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88813fe397c0 RBP: 0000000000000001 R08: ffff88813fe397c7 R09: 1ffff11027fc72f8 R10: dffffc0000000000 R11: ffffed1027fc72f9 R12: 0000000000000001 R13: dffffc0000000000 R14: ffff88813fe397c0 R15: ffff88813fe397c0 FS: 0000000000000000(0000) GS:ffff888125566000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe3561456b8 CR3: 000000000e54c000 CR4: 00000000003526f0 Call Trace: use_temporary_mm+0x98/0x140 arch/x86/mm/tlb.c:1029 __text_poke+0x632/0x9a0 arch/x86/kernel/alternative.c:2581 text_poke arch/x86/kernel/alternative.c:2645 [inline] smp_text_poke_batch_finish+0xd36/0x1160 arch/x86/kernel/alternative.c:3034 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:899 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245